EP0810748B1 - Arrangement et procédé pour opérer et tester un dispositif optique - Google Patents
Arrangement et procédé pour opérer et tester un dispositif optique Download PDFInfo
- Publication number
- EP0810748B1 EP0810748B1 EP19960108813 EP96108813A EP0810748B1 EP 0810748 B1 EP0810748 B1 EP 0810748B1 EP 19960108813 EP19960108813 EP 19960108813 EP 96108813 A EP96108813 A EP 96108813A EP 0810748 B1 EP0810748 B1 EP 0810748B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- optical
- source
- signal
- tunable filter
- gain medium
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/07—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems
- H04B10/073—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems using an out-of-service signal
- H04B10/0731—Testing or characterisation of optical devices, e.g. amplifiers
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S5/00—Semiconductor lasers
- H01S5/10—Construction or shape of the optical resonator, e.g. extended or external cavity, coupled cavities, bent-guide, varying width, thickness or composition of the active region
- H01S5/1071—Ring-lasers
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/07—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/29—Repeaters
- H04B10/291—Repeaters in which processing or amplification is carried out without conversion of the main signal from optical form
- H04B10/2912—Repeaters in which processing or amplification is carried out without conversion of the main signal from optical form characterised by the medium used for amplification or processing
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S5/00—Semiconductor lasers
- H01S5/50—Amplifier structures not provided for in groups H01S5/02 - H01S5/30
Definitions
- This invention relates to an optical source according to the preamble to claim 1.
- test devices with multiple wavelengths applied at the same time.
- Such devices are, for example, EDFA's used in wavelength division multiplexing (WDM) applications.
- WDM wavelength division multiplexing
- Tunable Fiber Ring Lasers with an Electrically Accessible Acousto-optic Filter discloses a tunable fiber ring laser with wavelength controllable from 1285 to 1367 nm by changing the frequencies of the acoustic shear waves in acousto-optic filters.
- a gain medium is coupled to an acousto-optical filter in a ring configuration by means of polarization maintaining fibers.
- Rankin et al in Electronics Letters, Vol. 31, No. 25, 7 December 1995, page 2175/2176, XP 000546800, "Agile, tunable, chirped laser with low background emission” discloses a unidirectional ring configuration with polarization maintaining fibers connecting an acousto-optic tunable filter and a gain chip/beam splitter module, which contains an isolator, a polarizer, and gradient index lenses. To span the optical tuning range, the acousto-optical tunable filter is driven by a radiofrequency sweeper, thus determining the wavelength of the optical source.
- the optical source according to the invention is in particular suitable for a multiplexed laser source which generates multiple wavelengths so that the component, device or system under test, having a recovery time, reacts in the same way, as it does when many single laser sources are applied at the same time.
- a multiplexed laser source is described in the older application EP-A-716515 (by the same applicant) which has been published after the application date of the present invention.
- the multiple wavelengths generated by a tunable laser or another source are time multiplexed so fast that the component, device or system under test, having a recovery time, does not recognize that the different wavelengths are applied one after the other.
- the device under test can be any optical device in the field of laser technology which exhibits the mentioned recovery time, such as optical devices in optical communication networks, biological and chemical substances, particularly cells and DNA-structures and photosensitive drums in laser printers etc.
- the device under test is an optical amplifier, in particular an erbium-doped fiber amplifier (EDFA) or a praseodymiumdoped fiber amplifier (PDFA).
- EDFA erbium-doped fiber amplifier
- PDFA praseodymiumdoped fiber amplifier
- An important parameter to measure is the gain and noise figure of this amplifier.
- this amplifier may be used in wavelength division multiplexed systems. In the current state, these systems use four different channels (wavelengths) to transmit optical signals. Thus, for a complete operational test of the amplifier, four optical signals with different wavelengths have to be applied for operation and testing. Due to the physics of the EDFA, the recovery time from the noise level with signal applied to the amplifier to the noise level without signal is slow, i.e.
- the noise level increases from a very low level to a stable level.
- four different wavelengths generated by a single tunable laser are applied, one after the other, to the device under test within its recovery time, so that the device under test does not recognize that there is only one wavelength signal present at a time.
- all different wavelengths are applied within a time interval from 10 to 30 microseconds, particularly 12-15 microseconds, i.e. at low recovery.
- the main advantage of the multiplexed laser source is that one single fast multiplexed tunable laser source is sufficient to operate a device with several channels or to perform the same measurements as a set of laser sources, each generating a signal with a single wavelength.
- the operation of the mentioned tests at multiple wavelengths can be performed less expensive and more easily than by a set of lasers.
- a tunable laser may be used to generate the multiple optical signals for the multiplexed laser source.
- a tunable laser allows generation of optical signals with different wavelengths, one after the other.
- the control input of the tunable laser may be connected to the output of a pattern generator.
- the pattern generator multiplexes the multiple different wavelength signals generated by the tunable laser.
- the pattern generator enables adjustment over a wide range of the time interval between switching from one wavelength to another of the signals generated by the tunable laser.
- the pattern generator can be substituted by any other device which switches the tunable laser from one wavelength to another within low recovery of the device under test.
- a source generating several wavelengths at the same time may also be used instead of the multiplexed laser source.
- a rotating set of filters transparent at the different wavelengths at which the device operates are disposed between the output of the white light source and the input of the optical component, device or system to be tested. The rotation of the set of filters is carried out in such a manner that the different wavelengths of the light generated by the source are applied to the device under test or under operation, one after each other, within the recovery time of the device under test.
- the optical device to be tested or to be operated is preferably an amplifier, in particular an erbium-doped fiber amplifier (EDFA) which can be used in wavelength division multiplexing applications and works under multiple wavelengths simultaneously.
- EDFA erbium-doped fiber amplifier
- Fig. 1 shows a known arrangement for testing various parameters of an erbium-doped fiber amplifier (EDFA) 2.
- EDFA erbium-doped fiber amplifier
- the output of a tunable laser 1 is connected with the input of EDFA 2 via an optical fiber 4.
- the output of EDFA 2 is connected with the input of an optical signal analyzer (OSA) 3 via an optical fiber 5.
- OSA optical signal analyzer
- the tunable laser 1 is switched to a first wavelength for a first measurement.
- the optical signal analyzer 3 analyzes the various parameters of the EDFA, particularly gain and noise, and displays them to the operator.
- the operator switches the tunable laser source 1 to a second wavelength and so on.
- Fig. 2 is a block diagram of an apparatus arrangement for testing an optical device according to the invention.
- the output of a tunable laser 1 is connected with the input of the EDFA 2 via an optical fiber 4.
- the output of the EDFA is connected with the input of an optical signal analyzer (OSA) 3 via an optical fiber 5.
- the arrangement according to the invention further comprises a pattern generator 6.
- the output of the pattern generator 6 is connected via an electrical cable 7 with the control input of the tunable laser 1.
- the output signal of pattern generator 6, which will be described in more detail with regard to Fig. 3, controls the tunable laser 1 which generates multiple optical signals with different wavelengths ⁇ 1, ⁇ 2, ⁇ 3 and ⁇ 4. These multiple signals generated by the laser source 1 and applied to the optical fiber 4 are displayed in diagram 8.
- the diagram 8 shows the appearance of the multiple wavelengths ⁇ 1 to ⁇ 4 generated by the laser source 1 as a function of time t.
- the laser source 1 With the aid of the pattern generator 6, the laser source 1 generates a signal with the wavelengths ⁇ 1 at a time t1. Then the tunable laser 1 switches the signal with the wavelength ⁇ 1 off and switches a signal with the wavelength ⁇ 2 on at a time t2. In the next step, the laser source 1 switches the signal with the wavelength ⁇ 2 off and switches a signal with the wavelength ⁇ 3 on at a time t3. Then the laser source 1 switches the signal with the wavelength ⁇ 3 off and switches the signal with the wavelength ⁇ 4 on at a time t4. It will be understood that instead of a pattern generator any other device can be used which controls a tunable laser in the same manner as described.
- more or less signals with different wavelengths can be generated by one or more tunable lasers depending on the wavelengths the device under test operates with.
- the time intervals between the different signals with the wavelengths ⁇ 1 to ⁇ 4 can be modified in a way that they are different.
- the time interval in which a first signal is switched on can be longer than other time intervals.
- the power of the different signals can also be adjusted to different magnitudes. A wide range of variation of the different characteristics of the different signals and their time correlation allows to operate the device under test under various conditions in accordance with how they appear in practice. Many different test patterns can be memorized in the pattern generator.
- All of the signals with different wavelengths ⁇ 1 to ⁇ 4 appear in a time interval t1 to t4 which is in the time interval of the recovery time of the amplifier 2. It will be understood that it is within the scope of the invention to generate various signals with different wavelengths within the recovery time of the specific device under test.
- Fiber amplifiers are active optical components generating a noise signal at their output depending on the input signal and time.
- the signal When an optical signal is applied at the input of such amplifiers, the signal leads to a stimulated emission of photons - if the laser condition is fulfilled.
- the output signal is strong, since most of all photons are in a high energy level and are used to amplify the input signal which stimulates the photons to change their energy to a lower level and resulting to the emission of light which is coherent with the light at the input of the amplifier. Accordingly, there is only a low amount of photons in the high energy level available for a spontaneous emission of light. Thus, the noise level is low.
- the stimulation of photons stops.
- the amplifier still pumps the photons to a high energy level and since no photons are stimulated, the amount of photons which are available for a spontaneous emission of light (noise) increases during the mentioned recovery time.
- the noise signal increases from a very low level to a stable level.
- An optical source 51 according to the invention shown in Figure 5 and which will be described later on in more detail, generates multiple optical signals and needs only a few microseconds to switch from one wavelength to another. Within this time interval, the noise level of the amplifier remains (nearly) at the same noise level like before switching off the input signal. Thus, due to the physics of the amplifier, the amplifier under test shows the same behavior under the set of test signals within the recovery time of the amplifier as under conditions in practice, where multiple signals with different wavelengths are present at the same time.
- the recovery time of the erbium-doped fiber amplifier 2 (EDFA) is in the range of 10 ms.
- Fig. 3 depicts the control signal generated by the pattern generator 6 in Fig. 2 as a function of time.
- the control signal 20 which is applied to the laser source 1 comprises four steps 21 to 24 at different signal levels.
- the pattern generator 6 starts generating a control signal.
- the controlled laser source 1 When the signal level reaches a certain value, the controlled laser source 1 generates a signal with a wavelength ⁇ 1 for a short time as shown in Fig. 2. Then the control signal is kept constant from edge 9 to edge 10 as indicated by the first step 21.
- the control signal drops at a time t6 which is shown at edge 10 the tunable laser 1 generates a signal with the wavelength ⁇ 2 for a short time.
- control signal is kept constant from the time interval t6 to t7 indicated by the second step 22.
- the laser source 1 generates a signal with the wavelength ⁇ 3 for a short time.
- the control signal is again kept constant as indicated by the third step 23.
- the control signal 20 drops again, switching the tunable laser 1 to generate a signal with the wavelength ⁇ 4 for a short time.
- the control signal 20 is kept constant as shown by the fourth step 24 and at a time t9, indicated by edge 13 the pattern generator starts repeating the described control signal.
- control signal 20 can be easily modified if a tunable laser is used having different control signals than that described.
- the time interval t5 to t9 is significantly lower than 10 ms to test the erbium-doped fiber amplifier 2 with a recovery time ⁇ 10 ms. Accordingly, the frequency of the sequence of the steps 21 to 24 is significantly higher than 100 Hz, to operate the optical device at low recovery.
- Fig. 4 shows a block diagram of a second arrangement for testing an optical device 2 comprising a further laser 40 with regard to Fig. 3, being separately adjustable.
- Fig. 4 comprises a further laser 40, an optical fiber 41 and optical coupling means 42 coupling optical fiber 4 and optical fiber 41 to the input of the device under test, being an optical amplifier 2.
- tunable laser 1 generates optical signals with the wavelengths ⁇ 1 , ⁇ 2 and ⁇ 3 .
- An optical signal with the wavelength 4 ⁇ is generated by the separately adjustable laser 40.
- the arrangement according to Fig. 4 enables an optical signal with the wavelength ⁇ 4 to be generated separately which allows modification of the optical signal, appropriate to the test conditions.
- further lasers can be used to substitute the optical signals generated by the time multiplexed tunable laser 1 to increase the degree of freedom in adjusting the test conditions.
- an optical device such as an erbium-doped fiber amplifier
- a time multiplexed tunable laser source being triggered by signals to be transmitted optically (not shown).
- a tunable laser is triggered by a pattern generator but a further laser is triggered by the signals to be transmitted optically.
- Fig. 5 shows an optical source 51 (a tunable laser), according to the invention, generating multiple optical signals to be applied to the device under test, such as an EDFA or PDFA having a recovery time.
- an optical source 51 a tunable laser
- Source 51 comprises a control unit 52, a gain medium 53, an electrically tunable filter 54, such as an acousto optical tunable filter (AOTF), a radio frequency generator 55, an adjustable source of current 56, a monitor unit 57 and beam splitters 58 and 59.
- Control unit 52 is equipped with a digital to analog converter and an analog to digital converter.
- Control unit 52 is connected with a data processor unit, such as a computer (PC) or the like and/or a pattern generator (not shown in Fig. 5). These means allow to trigger the control unit 52 to generate two output signals.
- PC computer
- the first output signal adjusts the current source 56.
- the source of current 56 Depending on the input signal of the control unit 52 from the data processor unit and/or pattern generator, the source of current 56 generates a current which is applied to the gain medium 53, such as a semiconductor amplifier, generating a coherent optical signal.
- the power level of the optical signal depends on the applied current.
- the second output signal adjusts the radio frequency generator 55.
- the generator 55 Depending on the input signal of the control unit 52, the generator 55 generates an output signal with a certain frequency which is applied to the AOTF 54.
- the frequency characteristic of the AOTF depends on the frequency applied to the AOTF.
- Gain medium 53 and electrically tunable filter 54 each have an input and an output for optical signals.
- the output of the gain medium 53 is connected with the input of the electrically tunable filter 54 via a fiber 59a.
- the output of the tunable filter 54 is connected with the input of the gain medium 53 via a fiber 59b.
- the connections between gain medium 53 and tunable filter are preferably made via polarization maintaining fiber (PMF) and in parallel beam.
- PMF polarization maintaining fiber
- gain medium 53, tunable filter 54 and fibers 59a, 59b are arranged to build up a ring cavity structure.
- a beam splitter 59 for output power coupling is arranged in the ring cavity structure, preferably in the vicinity of the output of the gain medium 53.
- One end of fiber 59c is connected with beam splitter 59, while the other end 59d passes a second beam splitter 58 and is applied to the device under test (not shown in Fig. 5).
- One end of a fiber 59c is connected with the beam splitter 58 and the other end leads a part of the output signal of optical source 51 to a monitor unit, such as a monitor diode 57.
- Monitor diode 57 generates an electrical signal, dependent on the frequency and the intensity of the output signal of the optical source 51.
- Monitor diode 57 is connected with the control unit 52, in order to make optical source 51 to a selfadjusting system. It will be understood that the selfadjustment may be carried out by the control unit 52 itself and/or by a data processor (not shown) when using a comparator (not shown) comparing the desired signal values with the actual signal values
- Fig. 6 shows a diagram with output laser power of the signals with different wavelengths which are generated by the optical source in Fig. 5.
- wavelengths tuning is achieved by an acousto optical tunable filter (AOTF) 54 as a wavelength filter.
- AOTF acousto optical tunable filter
- a change in wavelength as shown in Fig. 6 is achieved by changing the radio frequency (RF) of radio frenquency generator 55. According to the invention, this can be done very fast, therefore a change in the range of 10 microseconds is possible.
- a change in power when switching to another wavelength as shown in Fig. 6 is carried out by changing the drive current of the semiconductor gain medium 53.
- a change in wavelength and an individual power setting for each wavelength can be carried out within about 12-15 microseconds.
- number of settable wavelengths recovery time of the devices under test/wavelengths and power setting time for each wavelength.
Landscapes
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Lasers (AREA)
- Optical Communication System (AREA)
- Testing Of Optical Devices Or Fibers (AREA)
Claims (7)
- Une source optique (51) comprenant ;
- La source optique selon la revendication 1, dans laquelle ledit milieu à gain optique, ledit filtre accordable électriquement et lesdites fibres de conservation de polarisation constituent une cavité annulaire.
- La source optique selon la revendication 1, dans laquelle l'unité de surveillance (57) est une diode de surveillance.
- La source optique selon l'une quelconque des revendications précédentes, dans laquelle le milieu à gain optique (53) est un amplificateur à semi-conducteur.
- La source optique selon l'une quelconque des revendications précédentes, dans laquelle le filtre accordable électriquement (54) est un filtre accordable opto-acoustique.
- Un dispositif de génération de signaux optiques ayant différentes longueurs d'onde, comprenant ;
- Un dispositif de mesure du bruit d'un dispositif optique (2), ledit dispositif optique étant du type utilisé pour amplifier simultanément une pluralité de signaux optiques ayant des longueurs d'onde différentes, le dispositif comprenant ;
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE1996612187 DE69612187T2 (de) | 1996-06-01 | 1996-06-01 | Vorrichtung und Verfahren zum Betreiben und Prüfen einer optischen Vorrichtung |
EP19960108813 EP0810748B1 (fr) | 1996-06-01 | 1996-06-01 | Arrangement et procédé pour opérer et tester un dispositif optique |
US08/689,973 US5825530A (en) | 1994-12-02 | 1996-08-16 | Arrangement and method for operating and testing an optical device |
JP13702297A JPH1065250A (ja) | 1996-06-01 | 1997-05-27 | 光学装置を動作させあるいは試験するための装置と方法 |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP19960108813 EP0810748B1 (fr) | 1996-06-01 | 1996-06-01 | Arrangement et procédé pour opérer et tester un dispositif optique |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0810748A1 EP0810748A1 (fr) | 1997-12-03 |
EP0810748B1 true EP0810748B1 (fr) | 2001-03-21 |
Family
ID=8222840
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP19960108813 Expired - Lifetime EP0810748B1 (fr) | 1994-12-02 | 1996-06-01 | Arrangement et procédé pour opérer et tester un dispositif optique |
Country Status (3)
Country | Link |
---|---|
EP (1) | EP0810748B1 (fr) |
JP (1) | JPH1065250A (fr) |
DE (1) | DE69612187T2 (fr) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0905490B1 (fr) * | 1998-04-21 | 2001-01-17 | Hewlett-Packard Company | Contrôleur de composantes optiques |
DE19963803A1 (de) * | 1999-12-30 | 2001-07-26 | Siemens Ag | Verfahren und Anordnung zur Einstellung der Frequenz eines Sendelasers |
CA2964464A1 (fr) * | 2014-10-14 | 2016-04-21 | The Arizona Board Of Regents On Behalf Of The University Of Arizona | Reseaux de transmission optique equilibres a multiples longueurs d'onde |
CN111901053B (zh) * | 2020-07-14 | 2022-08-30 | 武汉高思光电科技有限公司 | 快速edfa测试系统及方法 |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3203611B2 (ja) * | 1994-02-14 | 2001-08-27 | 日本電信電話株式会社 | 雑音指数測定方法および装置 |
DE69419925T2 (de) * | 1994-12-02 | 1999-12-02 | Hewlett Packard Gmbh | Vorrichtung zur Generierung von optischen Signalen mit unterschiedlichen Wellenlängen und Vorrichtung und Verfahren zum Betreiben und Prüfen einer optischen Vorrichtung |
-
1996
- 1996-06-01 DE DE1996612187 patent/DE69612187T2/de not_active Expired - Fee Related
- 1996-06-01 EP EP19960108813 patent/EP0810748B1/fr not_active Expired - Lifetime
-
1997
- 1997-05-27 JP JP13702297A patent/JPH1065250A/ja active Pending
Also Published As
Publication number | Publication date |
---|---|
EP0810748A1 (fr) | 1997-12-03 |
DE69612187D1 (de) | 2001-04-26 |
JPH1065250A (ja) | 1998-03-06 |
DE69612187T2 (de) | 2001-07-19 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US6538778B1 (en) | Optical component tester | |
US5173794A (en) | Wavelength division multiplexing using a tunable acousto-optic filter | |
US5825530A (en) | Arrangement and method for operating and testing an optical device | |
JP3462938B2 (ja) | 波長多重時の雑音指数測定方法および測定装置 | |
US5521751A (en) | Noise measurement for optical amplifier and a system therefor | |
EP1965518B1 (fr) | Dispositif de détection de crêtes dans une lumière à multiplexage en longeur d'onde et appareil pour contrôler la dite lumière | |
JPH11506871A (ja) | 光ファイバレーザーシステム及び対応するレイジング方法 | |
US6404798B1 (en) | Low noise and wide power range laser source | |
CA2222002A1 (fr) | Methode et circuit de detection des changements de mode dans l'utilisation du laser | |
US6862303B2 (en) | Multiwavelength locking method and apparatus using acousto-optic tunable filter | |
US7274870B2 (en) | Apparatus and method for simultaneous channel and optical signal-to-noise ratio monitoring | |
EP2409369B1 (fr) | Un dispositif générateur de peigne de longueurs d'onde optique | |
EP0810748B1 (fr) | Arrangement et procédé pour opérer et tester un dispositif optique | |
JP3479468B2 (ja) | 波長分割多重化システムにおける光学伝送信号の光学パワーの制御方法 | |
EP0851205B1 (fr) | Interféromètre optique et synthétiseur de signal utilisant l'interféromètre | |
EP0716515B1 (fr) | Arrangement pour générer des signaux optiques avec différentes longueurs et arrangement et procédé pour opérer et tester un dispositif optique | |
JP2002318827A5 (fr) | ||
JP2002031786A (ja) | コヒーレント多波長信号発生装置 | |
US6377378B1 (en) | Suppression of polarization hole burning with an acousto-optic modulator | |
JP2006208656A (ja) | 光周波数コム発生方法、光周波数コム発生装置及び高密度波長多重送信システム | |
JPH10209973A (ja) | 光波長多重送信回路 | |
JP2757816B2 (ja) | 光強度変調器の特性測定方法及び制御方法 | |
JP2004294543A (ja) | 周期的多波長光発生装置 | |
KR100305106B1 (ko) | 이득평탄도모니터링및제어장치를구비한광섬유증폭기 | |
Raybon et al. | A reconfigurable optoelectronic wavelength converter based on an integrated electroabsorption modulated laser array |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): DE FR GB |
|
17P | Request for examination filed |
Effective date: 19980509 |
|
17Q | First examination report despatched |
Effective date: 19990223 |
|
GRAG | Despatch of communication of intention to grant |
Free format text: ORIGINAL CODE: EPIDOS AGRA |
|
GRAG | Despatch of communication of intention to grant |
Free format text: ORIGINAL CODE: EPIDOS AGRA |
|
GRAH | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOS IGRA |
|
GRAH | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOS IGRA |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): DE FR GB |
|
RAP2 | Party data changed (patent owner data changed or rights of a patent transferred) |
Owner name: HEWLETT-PACKARD COMPANY, A DELAWARE CORPORATION |
|
RAP2 | Party data changed (patent owner data changed or rights of a patent transferred) |
Owner name: AGILENT TECHNOLOGIES, INC. |
|
REF | Corresponds to: |
Ref document number: 69612187 Country of ref document: DE Date of ref document: 20010426 |
|
ET | Fr: translation filed | ||
RAP2 | Party data changed (patent owner data changed or rights of a patent transferred) |
Owner name: AGILENT TECHNOLOGIES INC. |
|
RAP2 | Party data changed (patent owner data changed or rights of a patent transferred) |
Owner name: AGILENT TECHNOLOGIES INC. A DELAWARE CORPORATION |
|
RAP2 | Party data changed (patent owner data changed or rights of a patent transferred) |
Owner name: AGILENT TECHNOLOGIES, INC. (A DELAWARE CORPORATION |
|
REG | Reference to a national code |
Ref country code: GB Ref legal event code: IF02 |
|
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
26N | No opposition filed | ||
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: GB Payment date: 20050525 Year of fee payment: 10 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: FR Payment date: 20050617 Year of fee payment: 10 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 20050801 Year of fee payment: 10 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GB Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20060601 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20070103 |
|
GBPC | Gb: european patent ceased through non-payment of renewal fee |
Effective date: 20060601 |
|
REG | Reference to a national code |
Ref country code: FR Ref legal event code: ST Effective date: 20070228 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: FR Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20060630 |